Research on facial expressions has shown that people are more easily conditioned to fear facial expressions of than other types of expressions.

People are more easily conditioned to fear facial expressions of anger than other types of expressions. Various investigations about facial expressions have shown that diverse expressions are universal, that is, all cultures present them. Also, people respond in the same way to various facial expressions. The most common facial expressions are joy, sadness, anger, and fear.

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Bthreatening to ally with germany